Wastewater Practice Exam Questions and Answers | Latest Version | 2025/2026 | Correct & Verified

Wastewater Practice Exam Questions and Answers | Latest Version | 2025/2026 | Correct & Verified What is the primary purpose of a wastewater treatment plant? To remove contaminants from sewage and produce safe effluent for discharge. Why is screening used at the beginning of wastewater treatment? To remove large solids and debris that could damage equipment. What is the function of a grit chamber? To settle out sand, gravel, and other heavy particles. Why is primary sedimentation important in wastewater treatment? To remove settleable solids and reduce organic load. What is the purpose of aeration in secondary treatment? To provide oxygen for microorganisms to degrade organic matter. 2 Why is sludge digestion performed? To stabilize sludge and reduce pathogens before disposal. What is BOD and why is it measured? Biochemical Oxygen Demand; it indicates the organic pollution level in wastewater. Why is TSS (Total Suspended Solids) monitored in effluent? To assess solids removal efficiency and water clarity. What is the purpose of chlorination in wastewater treatment? To disinfect and kill pathogenic microorganisms. Why is pH control important in wastewater treatment? To optimize chemical reactions and biological processes. What is the difference between primary and secondary treatment? Primary removes settleable solids; secondary removes dissolved and suspended organic matter biologically. 3 Why are aerated lagoons used in wastewater treatment? To provide oxygen for microbial treatment in a simple, cost-effective system. What is nitrification in wastewater treatment? The biological conversion of ammonia to nitrate by bacteria. Why is denitrification important? To convert nitrates into nitrogen gas and prevent eutrophication in receiving waters. What is the purpose of a clarifier in secondary treatment? To allow activated sludge to settle and separate from treated water. Why is monitoring dissolved oxygen critical in aeration tanks? To ensure sufficient oxygen for microbial degradation